Optical device for producing a substantially stationary image of successive similar areas on a running web



HoRToN 2,155,013 OPTICAL DEVICE FOR PRODUCING A SUBSTANTIALLY STATIONARY April 18, 1939;

IMAGE OF SUCCESSIVE SIMILAR AREAS ON A RUNNING 'WEB Filed Aug. 6, 1935 2 Sheets-Sheetul Apnl 18, 1939. A, 1- Hom-ON 2,155,013

OPTICAL DEVILCE FOR PRODUCING A SUBSTANTIALLY STATIONARY IMAGE OF SUCCESSIVE SIMILAR AREAS ON A RUNNING WEB Filed Aug. 6, 14935 2 Sheets-Sheet 2 Patented Apr. 18, 1939 PATENT OFFICE OPTICAL DEVICE FOR PRODUCING A SUB- STANTIALLY STATIONABY MAGE F SUCCESSIVE SMLAR AREAS 0N A RUN- NING'WEB Albert J. Horton, White Plains, N. Y., assignorto E. Hoe & Co., Inc., New York, N. Y., a corporation of New York Application August 6, 1935, Serial No. 34,886

13 Claims.

'I'his invention relates to devices for observing impressions on a moving web or sheet, and more particularly to such a device'adapted for use in inspecting the registration of printed impressions on a running web in a printing machine in which the web is rewound into a roll.

In printing processes where the printed web is rewound into a roll,"it is desirable that an in` spection' be made of the alignment and registration of the printed impressions before rewinding, and when the web is traveling at high speed,

such inspection is impossible by direct observation of the movingweb. 1 In multi-colorprinting,

wherein theimpressions from one printing cylinder must register `with those from another, frequent inspection is required' in order to be certain that the impressions register and are correctly aligned, so that printing of high quality will be produced..

The improvements contemplated by this invention are particularly applicable to devices whereby successive marks or impressions on the printed and running web are reected (just prior to its being rewound) to a stationary viewpoint by a suitable reflecting member which is moved in synchronism with the running web so that the aforesaid marks or impressions will appear stationary and thereby permit close inspection thereof. A device` of this kind is disclosed in applicants pending application Serial Number 743,214, filed September 8, 1934, and the mecha nism herein shown and described includes certain refinements that resulted from further development of the invention previously disclosed.

One oi' the principal objects of this invention is to provide improved means to inspect the registration of a succession of regularly appearing printed impressions on a running web. l

Another object is to provide a mechanism, having the above mentioned means included in its structure, and whereby the same may be moved transversely relatively to the running web to observe and inspect any portion thereof across the same and to be disposed in a position convenient to the observer.

Still another object is to provide mechanism for Athe stated purpose, whereby successive portions of impressions appearing more than once per printing cylinder revolutionA may be inspected. Affurther object is to provide means to compensate for and rectify optical errors incident to theoperatio'n of devices of this description.

With the foregoing and other objects in view, which;will appear as the description proceeds,

the invention resides in the combination and arrangement of parts, and in the details of construction hereinafter described and claimed.

I The )referred v'embodiment of the invention is -illustrated in the accompanying drawings, wherein:

Figure 1 is an elevational view of a mechanism embodying the features of this invention, and which is 'shown disposed in operative relation to a running `W'ebfof a printing machine;

Figure 2 is an end view of the same;

Figure 3 is a sectional view on line 34-3 of Figurel; I

Figure'l4 is an elevational view of the main elements of the mechanism with a diagrammatic showing of its operation;

. Figure 5 is an enlarged detail view of the cooperating reflecting members and showing the optical error compensating and rectifying means associated therewith;

Figure 6 is a front face View of the parts shown in Figure 5;

Figure 7 shows a somewhat modified form of mechanism embodying certain features of this invention;

Figure 8 is a diagrammatic view depicting the drive connection between a driven web roller and the rotary reflecting member;

Figure 9 shows another modified forml of mechanism embodying certain features of this invention; and

lFigure 10 is a sectional View taken on the line IO-I of Figure 9. y

The mechanism illustrated in Figures 1, 2, and 3 comprises a supporting frame II mounted for movement transversely in front of the path of a web I2, which is led from a printing machine and passes around guide rollers I3 and I4, from` whence it is directed to a rewinding device (not shown) To facilitate the movement of the frame II, a pair of rollers I5 is provided at each end thereof which are adapted to support the frame II upon a track I6 secured to an adjacent beam Additional guide rollers I8 may be provided in back of the web I2 to steady it and prevent it vibrating during its travel between the rollers I3 and I4. The rollers I3 and I 4, it Will be understood may be driven parts of the machine operating upon the web I2 to feed the web to the rewinder.

'A light reflecting member or mirror I9 is mountedat one end of the frame II by brackets 2| in position to receive and reflect the light rays from impressions upon the printed web I2 to an image observing means 22. The observing means 422 is'preferably enclosed within a box 23 which is mounted upon the frame II adjacent the end thereof, opposite the mirror I9. The observing means 22 may be mounted upon frame II for movementl toward and away from the mirror I9 so thatI it may be moved into the position indicated by the dotted lines 24. The mirror I9 is of suiiicient length to reflect light rays from a lengthwise strip of the web I2, that is at least equal in length to the circumference of a form cylinder of the printing machine, and the frame Il is permitted sufficient movement across the web i2 to permit the mirror I9 to be properly positioned to reflect the light rays from a spot in any desired widthwise area from one edge of the web to the other. As illustrated, the face of the mirror I9 is disposed at an angle to the web I2 so as to reflect the light rays to a point 'along a line parallel to the face of the web.

The impression observing means 22, enclosed in the box 23 in Figure 1, and shown in larger scale in Figures 4, 5, and 6, comprises a rotor 25, having a plurality of light reflecting surfaces or mirrors 26 upon its periphery, a rectifying member or mirror 21, and an image magnifying device 28. The rotor 25 is rotated in synchronism with the printing machine to cause each of the reflecting surfaces to follow a desired impression on the web i2 during its travel from roller I3 to roller I4. The rotor may be rotated by means of a motor 29 of the kind shown in the hereinbefore mentioned prior application, or by a chain or a flexible shaft 3l, driven from the printing machine, either means serving to rotate a worm 32 and worm wheel 33, the latter being secured on the shaft 34, supporting the rotor 25. The shaft 34 is journaled in standards 35, extending upwardly from a base 36 which may be secured to the box 23 or directly mounted upon suitable supporting means for movement toward and away from either the mirror I9 of Figure 1, or the web I2 of Figure 4.

It will be understood that the flexible shaft 3|, or chain drive, when used, is drivingly connected to a suitable rotating member of the machine,

which may be the roller I4, as depicted in Figure.

8, so that the worm 32, and therefore the worm wheel 33 and rotor 25 will be rotated at the proper speed. A preferred mechanism for connecting the flexible shaft 3| to the driven web guide roller I4, or other rotating component of the printing machine, includes a beveled gear I4 secured for rotation with the roller I4 and meshing with a similar beveled gear 3| secured to the exible shaft 3| for rotation therewith.

The motor 29 shown in Figure 4, and the flexible shaft 3| shown in Figure 6, are mounted upon the base 36 with provision for movement from right to left as shown in Figures 4 and 6, and vice versa, and transmit this movement to the worm 32. The motor shaft 31 has its outer terminal journaled in a bearing 33 formed as part of the base 36 and is mounted for axial movement in this bearing. The above movement of motor 29 and shaft 31 may be obtained by rotating a handle 39 secured to a screw 4I, which is journaled in the base 35 and threadingly engages a motor support 42. Axial movement of the worm 32, will cause it to operate as a rack in respect to the gear 33 and the rotor may thus be advanced or retarded to bring a spot in any desired area lengthwise of the web into view.

In the form depicted in Figure 6, the worm y shaft 31' is mounted for rotation and axial movement in the bearing 35 and for rotation in a movable bearing 42' which is movable relative to the base 35 and is actuated by the screw mechanism which moves the motor support 42. The shaft 3.1' is held against axial movement relative to the bearing 42 so that movement of the bearing, similar to the described movement of the motor support 42, moves the shaft 31' axially in the bearing 38 to advance or retard the Vrenecting rotor, as hereinbefore disclosed. If desired. the adjusting mechanism may be modified to move the worm 32 along a feather on the shaft 31, which latterwould then be held against axial movement.

The light rays received by the reecting surfaces 26 are reflected therefrom to the rectifying mirror 21 which is supported upon a rock shaft 43 journaled at its ends in extensions 44 of the standards 35. The shaft 43 may be rocked by a lever 45, one end of which is secured to the shaft. while the other end carries a cam roller 45 retained in engagement with the cam surface 41 of a cam 48. The cam 43 is secured to shaft 34 and rotates therewith. A spring 49 having an end secured to the lever 45 and the other end to an extension 44 maintains the roller 45 in operable engagement with the cam surface 41. The rectifying function of this portion of the mechanism will be hereinafter explained. The image magnifying device 28 receives the reflected light rays from the mirror 21 and by enlarging the images, assists the observer in their inspection.

The impression observing means 22 in the arrangements shown in Figures 1 and 4 require movement transversely of the web in order to view the desired impression. In many instances, the disposition of the` means 22 within the .frame of the printing machine may be inconvenient, obiectionable, or due to lack of space, impossible, and if desired, an arrangement such as shown in Figure 7 may be provided. In this arrangement, the rotor 25 is disposed to one side of the printed web I2 and light rays from the impressions on the web are reflected to the reflecting surfaces thereof, by means of cooperating light reflecting members or mirrors 5| and 52. The mirror 5I is adapted to receive the light rays from the impression on the web.

The mirrors are so arranged with respect to the web I2, rotor 25, and to each other, that the light rays received by mirror 5I are reflected to mirror 52, and thence to the surfaces 24 of the rotor. In order to inspect any desired impression across the web I2, the mirror 5| is moved transversely of the web by a feed screw 53 threadingly engaging a base member 54, upon which the mirror 5I is mounted. The feed screw 53 is journaled at both ends in a stationary part 55 and a guide slot or groove 56 is provided in the said part In which the base 54 is slidable. A handle 53a may 'mirrors 5I and 52, and the distance between the mirror 52 and the surface 25 must remain constant for best operating conditions, provision for maintaining it so is provided by a gear 51, secured to the end of the screw 53 and meshing with a gear 53 secured to the end of a similar screw 59, which is journaled at both ends thereof to the part 55. The screw 55, threadingly engages a base 5| for the mirror 52, whichbase slides in a groove 52 also formed in the part 55. Rotation of screw 53 to move the mirror 5I will rotate the screw 59 through the gears 51 and 53, and move the mirror 52 also, the gears and screws being so proportionedihat the movement 52 are arranged as shown, in order that the angular positions of the mirrors may be fixed with respect to their carrying bases, but it is obvious that? these mirrors may be arranged to move in parallel planes if the mechanism shown in Figures 9 and 10 is provided to turn them as they arel moved, and thus direct the light rays to the proper points. 'Ihis mechanism includes means for pivoting the vertical mirrors to turn in their bases 8| b`y providing suitably grooved ways 82 and 88 adjacent the paths of the respectivev mirrors and aV follower 84, on an arm 85 connected to each mirror by an interposed arm 86 and running in a groove. The bases 8| of the mirrors 80 are mounted on parallel threaded rods 81 and 88, adapted to be rotated by a handle 89 and connected together by gearing 9|. As in the form shown in Figure 7, the gears 9| and the threaded rods 81 and 88 are so proportioned that the' movement of the mirrorsv 80 will maintain the sum of the above mentioned distances at a constant value. Itis obvious that by such means, the vertical mirrors could be turned as they are moved in parallel planes and the light rays properly directed. L

The provision shown in Figure 1 whereby the observing means 22 is movable toward and away from the mirror I9, or as in Figure 4, the web |2, reduces or increases the range of the reflecting surfaces 26 as desired. A change in position of the means 22 is required when the same impressions occur at regular intervals, but at greater or lesser spacing along the web. For example, when the form cylinders of the printing machine each carry forms that are printed but once during each revolution of the form cylinder, the length of web run scanned by the device must equal the circumferential dimension of the form cylinder, but when the form cylinders are each provided with two identical forms, each extending half way around the cylinder, the impressions will occur on the web at twice the frequency, and this condition permits the movement of the observing means 22 closer to the web |2, or mirror I9, and the speed of rotation of member 25 to be increased, the distance between the reflecting surface 26 and the web or mirror being reduced by half and the speed of the rotation doubled. The position of the observing means shown in dotted lines in Figure 4 represents the latter condition, where the web run scanned is shorter. It is obvious that variation in the size of the form cylinders will 'also necessitate corresponding variation of the length of web run scanned and consequently variation of the distance oi the device from the web, for the angle embraced between the upper and lower dotted lines in Figure 4 is determined by the number of mirror faces on the rotor and does not change. When adjustments are properly made, the appearing and disappearing images match perfectly.

The function of the image rectifying mechanism which includes the oscillating mirror 21 and its operating members hereinbefore described, is to correct optical errors that would be present in the image seen in the magnifier 28 if the mirror 21 remained stationary. one factor that produces an error is that the path of the web where it is scanned by the device is a straight line and forms the chord of the sector -across the rotor sweeps.

The light rays from a spot at 1| (Figure 4),

strike one of the rotor mirrors 28 at a point 12 as indicated by line 13. Using the length of line 13 as a radius, when the rotor mirror has moved, for a certain period of time. the beam of light will have traveled lthrough a certain angle, and if the web were not present it would strike the point 14. The motion of the web in the same time will carry it from the point 1| to the point 15, which is seen to be some distance from the point at which a beam from the point 14 would intersect the path of the web. This condition causes a slight vertical reciprocation of the observed image which is repeated as,v each impression passes through the field of view. Another factor that would produce some error'is caused by the motion of the mirror faces 26 in an arc about the rotor axis, and this is superimposed on the error previously mentioned.

The contour of th cam surface 41 is so formed that the rocking motion imparted to the mirror 21 corrects these and other optical errors that would otherwise be present, and the rapidly moving successive images viewed through the magnifying means 28 appear to be absolutely stationary, and the slightest faults in register of the printing may easily be seen. y

It will be understood that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof,

to the claims rather than to the foregoing de-l scription to indicate the scope of the invention.

What I claim is:

l. In a mechanism ,for observing printed impressions on a running web and adapted to operate in timed relation with the running web, a first rotary member by which the web is driven, a rotary reflecting member having a worm wheel operably connected thereto, a rotatably driven worm in mesh with the worm wheel and operably connected to the first member to drive the refleeting member, and means to move the worm axially and thereby vary the relation of the reflecting member to the first member.

2. In combination with a mechanism for lobserving printed impressions on a running web and operable intimed relation with the running web, a rotatable reflecting member having a worm wheel operablyl connected thereto, a web driving member, a rotatable worm in mesh with said worm wheel and rotatably driven by said web driving `member thereby driving the rotatable reflecting member, and means bodily to move said worm axially to, vary the revolving relation between the said rotatable member and said web vdriving member.

' the eye of an observer, means for rotating the optical rectifier in timed relation with the running web, and separate means for oscillating the reflecting member in timed relation with the operable movement of the optical rectifier and the movement of the web to correct optical errors and produce a stationary image at the said viewpoint.

4. Means for observing an image of successive impressions equidistantly spaced on a printed web running in a straight observable path, including an optical rectifier mounted for rotary movement and having a plurality of light reflecting surfaces successively presented by its rotary movement to receive and reflect in succession light rays from the moving impressions, a light reflecting member mounted for controlled oscillatory movement relative to the said optical rectifier and positioned to receive light rays therefrom and reflect them to a fixed viewpoint in an area smaller than the said observable path and convenient to the eye of an observer, means for rotating the optical rectier in timed relation with the running web, and separate means for oscillating the reflecting member in timed relation with the operable movement of the optical rectifier and the movement of the web to correct optical errors and produce a stationary image at the said viewpoint.

5. Means for observing an image of successive impressions equidistantly spaced on a printed web running in a straight observable path, including an optical rectifier mounted for rotary movement and having a plurality of light reflecting surfaces successively presented by its rotary movement to receive and reflect in succession light rays from the moving impressions, a reflecting member mounted for variable oscillatory movement relative to the said optical rectifier and positioned to receive light rays therefrom and reflect them to a fixed viewpoint in an area smaller than the said observable path and convenient to the eye of an obsewenmeans for uniformly rotating the optical rectifier in timed relation with the running web, and means for operably oscillating the reflecting member in timed relation with the operable movement of the optical rectifier so that the angular movement of the reflecting member is accelerated during a phase of the movement of the web through the observable path and decelerated through other phases of the movement of the web through the observable path to correct optical errors and produce a stationary image at the said viewpoint.

6. A device for observing an image of successive similar equidistant impressions printed. in superposition on a web running in a straight observble path, an optical rectifier mounted for rotation and having a plurality of reflecting surfaces arranged in different planes, a light ray reflecting member mounted for cooperative Voscillatory movement relative to the optical rectiiier to receive light rays from the reflecting thereof and reflect them to the viewpoint of an observer in an area smaller than the said observable path, and mechanism to cooperably move the said optical rectifier and the said light ray reecting member to maintain them in light ray receiving and reflecting positions to cause the image to appear stationary at the said viewpoint.

7.1nadeviceforuseinobservingaprinted impression on a web or sheet moving in a straight path, a refiectingmember mounted for rotation and havinga plurality of light renecting sur- 4aimons faces on its periphery to reflect an image of the said impression, a gear mounted for rotation with the reflecting member, a worm mounted for rotation and axial movement and meshing with the gear to rotatably drive the reflecting member by the rotation of the worm, and means to axially move the said worm to adjustably rotate said reflecting member to thereby position the surfaces in desired relation to the impression.

8. In a device for observing printed impressions on a moving web, an optical rectifier, a

light defiecting member disposed to deflect light rays from the moving impressions to the optical rectier and the optical rectifier being constructed and arranged to reflect an image of the moving impressions to a xed point of observation. means for mounting the deflecting member and optical rectifier for movement as a unit across the web and mounting the rectifier for movement toward and away from the defiecting member.

9. In a device for observing printed impressions on a moving web, an optical rectifier, a light deiiecting member disposed to deflect light rays from the moving impressions to the optical rec-I tifier, the optical rectifier being constructed and arranged to reflect an image of the moving impressions to a fixed point of observation, a movable frame supporting the deiiecting member and the optical rectifier and mounted to move the defiecting member and optical rectier as a unit across the web, and means for mounting the optical rectifier for movement in the frametoward and away from the deflecting member.

10. In a device for observing printed impressions on a moving web, an optical rectifier, a light defiecting member disposed to deflect light rays from the moving impressions to the optical rectifier, the optical rectifier being constructed and arranged to reflect an image of the moving A impressions to avfixed point of observation, a

movable frame supporting the defiecting member and the optical rectiner and mounted to .move the deiieting member and optical rectifier asa unit across the web, means for mounting the optical rectifier for movement in the frame toward and away from the deiiecting member, and means for moving the optical rectifier toward and away from the defiecting member.

11. In a device for observing printed superposed register marks on a web moving in a straight observable path, a rotatable optical rectifier having a plurality of reflecting surfaces thereon, means to rotate the optical rectifier to reflect the light rays in succession from the moving register marks during their movement throughout the said observable path, a movable reecting member, and independent means for moving the reflecting member relative to the reflecting surfaces of the rotatable optical rectifier and in operable relation to the moving register marks lto reflect in succession light rays from the reflecting surfaces of the rotatable optical rectifier to a fixed point of observation so that a 'clear' image of the moving register marks ap- -pear at a fixed observation 'point smaller than plurality ot mirrors, a mirror mounted in iixed position on the frame and disposed to denect light rays from the moving impressions to the mirrors of the rotatable optical rectiiier. and the mirrors of the optical rectiner reiiecting an image of the movable impressions to a xed viewpoint o! observation, the optical rectifier being movably mounted in the frame tor movement toward and away from the iixed mirror.

ALBERT J. HORTON. 

